Figure 4

Treatment with anti-JAM-C antibody decreases the T-cell response. (a) Proliferation of spleen cells isolated from anti-JAM-C antibody-treated (n = 5) and isotype-matched control antibody-treated (n = 5) mice. Cells were restimulated in vitro with methylated bovine serum albumin (mBSA) (10 μg/ml, hatched columns) or concanavalin A (ConA) (5 μg/ml) or were left unstimulated (white columns). Results, expressed as fold increase in proliferation of stimulated over unstimulated cultures, represent the mean ± standard error of the mean (SEM) for each group of mice. Proliferation was significantly increased by stimulation with mBSA or ConA in cells isolated from isotype-matched control antibody-treated mice; *p < 0.05 versus unstimulated cultures. This proliferative response to mBSA and ConA was significantly reduced in cells of anti-JAM-C antibody-treated mice as compared to cells isolated from isotype-matched control antibody-treated mice; ^&p < 0.05 versus cells isolated from isotype-matched control antibody-treated mice with similar stimulation, as assessed by analysis of variance (ANOVA). (b) Interferon-gamma (IFN-γ) production by spleen cells isolated from anti-JAM-C antibody-treated (n = 5) and isotype-matched control antibody-treated (n = 5) mice. Cells were restimulated in vitro with mBSA (10 μg/ml, hatched columns) or ConA (5 μg/ml) or were left unstimulated (white columns). Results shown represent the mean ± SEM for each group of mice. IFN-γ production was significantly increased by stimulation with mBSA or ConA in cells isolated from isotype-matched control antibody-treated mice; *p < 0.05 versus unstimulated cultures. This IFN-γ response to mBSA and ConA was markedly reduced in cells of anti-JAM-C antibody-treated mice as compared to cells isolated from isotype-matched control antibody-treated mice; ^&p < 0.05 versus cells isolated from isotype-matched control antibody-treated mice with similar stimulation, as assessed by ANOVA. Serum levels of anti-mBSA total IgG (c), IgG1 ([d], left panel), and IgG2a ([d], right panel) on days 4 and 8 after intra-articular mBSA injection. Results shown represent the mean ± SEM for anti-JAM-C antibody-treated (n = 6, black columns) and isotype-matched control antibody-treated (n = 5, open columns) mice. *p < 0.05 versus control mice, as assessed by ANOVA. Ab, antibody; A.U., arbitrary units; Ig = immunoglobulin; JAM-C, junctional adhesion molecule-C; O.D., optical density.